You can find full records of the USA's Senate and House here: https://www.congress.gov/congressional-recordI’ve been looking for Huey Long’s 15 hour speech for a while for my timeline, but I can‘t seem to find the exact excerpts for the speech. Any luck finding any?
Specifically, the 74th Congress, covering the date of Long's filibuster, is here: https://www.congress.gov/congressional-record/74th-congress/browse-by-date
Scroll down to Volume 79, Part 8 (May 24, 1935 to June 13, 1935) and you'll find the Senate records for 12th June 1935 at the '9081 - 9191' link which takes you here: https://www.congress.gov/bound-congressional-record/1935/06/12/senate-section
There, you can download the entire text (43MB pdf) of proceedings that day, which includes Long's speech. From what I can see from a skim through, he starts on page 9089 and finishes at the bottom of page 9175 !
(His recipes for Southern-Fried Oysters and Pot-likker are on pages 9122-9123, if you're interested..., though if those are all you want, it's easier to find them here. )